Surgical bone anchoring devices and also a spinal column fixation system are known, for example, from U.S. Pat. No. 6,299,616. In the known system it is, however, necessary to use a torque wrench to tension the fixing element with a defined holding torque against the anchoring part in order to fix the bearing part immovably on the anchoring part in the implantation position. A further development of such bone anchoring devices is known from US 2009/0105718 A1. The fixing element disclosed therein comprises a predetermined break-off area between a distal and a proximal fixing element section. It serves the purpose of dispensing with a torque wrench. Therefore, only a tool receptacle for a screwing-in tool is provided on the proximal fixing element section. When, upon tensioning the fixing element against the anchoring part, the fracture torque specified by the predetermined break-off area is exceeded, the fixing element shears off between the distal and proximal fixing element sections. The distal fixing element section then holds the bearing part with a holding torque corresponding to the shear-off torque of the predetermined break-off area in a clamped manner on the anchoring part.
On the basis of the above prior art, the problem does, however, arise during a surgical procedure that it is very awkward to move the fixing element up to the bearing part and connect, in particular, screw the fixing element to the bearing part in order to tension the bearing part against the anchoring part. It is known to temporarily connect long guide sleeves to the bearing part in order to facilitate insertion of the fixing element and tools required for this. However, the connecting of guide sleeves to the bearing part is not very easy, particularly not when the view of the parts to be connected to one another is impeded and therefore requires great manual dexterity on the part of the surgeon. In addition, each surgical step involves more time.
Therefore, it would be desirable to provide an improved surgical bone anchoring device and an improved spinal column fixation system of the kind described at the outset that simplify a surgical procedure, in particular, the stabilization of a spinal column.